Repair or replace your AC? A guide for Miami-Dade homes

Published: 2026-10-11 · Kendall AC Repairs

When your AC breaks, the big question is whether it's worth fixing or better to put in a new one. There's no single answer, but a few questions make the decision much clearer.

1. How old is the unit?

In Miami's climate, a central AC usually lasts 10 to 15 years. If yours is under 8 years old, repairing it almost always makes sense. Past 12, replacement starts to make sense, especially for a major failure.

The manufacture date is usually on the outdoor unit label or can be decoded from the serial number.

2. What refrigerant does it use?

Very old units use R-22, a refrigerant that's no longer made and is expensive to find. If your unit uses R-22 and has a leak, repairing it is usually a poor investment.

More recent units use R-410A, and new models now come with newer refrigerants such as R-454B or R-32.

3. How much does the repair cost?

A rule of thumb: multiply the unit's age by the repair cost. If the result is over about 5,000, many technicians suggest considering replacement. For example, a 12-year-old unit with a $600 repair gives 7,200.

It's not a law, but it helps you avoid spending a lot on a unit near the end of its life.

4. How often has it broken down?

If you've called a technician several times in the last year, or it needs refrigerant every summer, the unit is costing you more than it seems.

5. How much is your electric bill?

A new efficient system can use much less electricity than a 15-year-old one. In a home where the AC runs almost all year, that monthly saving matters when deciding.

If you decide to replace it

• Ask for a proper size calculation for your home; bigger isn't always better.
• Confirm the contractor is Florida-licensed and pulls the county permit.
• Get the quote in writing, with permit and warranty included.
• Ask whether the ducts need replacing or repair.